Aug. i, 1921 
Wound-Cork Formation in the Sweet Potato 
647 
rapidly at 33 0 C. than at any other temperature tried. However, cork 
cells were formed at temperatures varying from 19.5 0 to 33 0 . A rela¬ 
tive humidity of from 95 to 100 is favorable for cork production. 
(4) No well-developed cork layer was produced over wounds under 
the conditions existing in the sweet-potato storage house. However, a 
dry, hard surface covering was formed through which infection by arti¬ 
ficial means could not be obtained. 
(5) The results of numerous experiments indicate that the healed sur¬ 
face of a wounded sweet potato forms a fairly efficient barrier against 
infection by microorganisms. 
LITERATURE CITED 
(1) Appel, Otto. 
1906. ZUR KENNTNIS DES WUNDVERSCHLUSSES BIJI DEN KARTOFFELN. Ill 
Ber. Deut. Bot. Gesell., Bd. 24, Heft 2, p. 118-122, pi. 9. 
(2) CouTant, Mary Wotherspoon. 
1918. wound periderm in certain cacti. In Bui. Torrey Bot. Club, v. 45, 
no. 9, p. 353-364, 3 fig., pi. 9. Literature cited, p. 364. 
(3) Harter, L. L., Weimer, J. L., and Adams, J. M. R. 
1918. SWEET POTATO STORAGE-ROTS. In Jour. Agr. Research, v. 15, no. 6, 
p. 337-368, pi. 21-27. Literature cited, p. 366-368. 
(4) Hauman-Merck, Lucien. 
1913. contribution A l’^tude des alterations microbiennes des organes 
charnus DES PLANTES. In Ann. Inst. Pasteur, t. 27, no. 7, p. 501-522. 
(5) Hawkins, Lon A., and Harvey, Rodney B. 
1919. physiological study of tiie parasitism of pytiiium debaryanum 
HESSE on THE potato TubER. In Jour. Agr. Research, v. 18, no. eg 
p. 275-298, pi. 35-37. Literature cited, p. 295-297. 
(6) Kny, Leopold. 
1889. UEBER DIE BILDUNG DES WUNDPERIDERMS AN KNOLLEN IN HIRER AB_ 
iiangigkeit von AUSSERN EINFLUSSEN. In Ber. Deut. Bot. Gesell., 
Bd. 7, p. 154-168. 
(7) Kuster, Ernest. 
1903. PATIIOLOGISCIIE PFLANZENANATOMIE IN III REN GRUNDZUGEN. Vli, 
612 p., 121 fig. Jena. 
( 8 ) - 
[1913]. PATHOLOGICAL PLANT ANATOMY . . . TRANSLATION BY FRANCES DOR- 
RANCE. Xiv, 258, 19 p. 
(9) MacMillan, H. G. 
1919. FUSARIUM-BLIGHT of potatoes under irrigation. In Jour. Agr. Re¬ 
search, v. 16, no. n, p. 279-304, pi. 37-41. Literature cited, p. 301- 
3 ° 3 - 
(10) Olufsen, Laurits. 
1903. UNTERSUCIIUNGEN UBER WUNDPERIDERMBILDUNG AN KARTOFFELKNOL- 
LEN. In Bot. Centbl., Beihefte, Bd. 15, Pleft 2, p. 269-308, 5 fig. 
Bibliographical footnotes. 
(n) Orton, W. A. 
1909. POTATO DISEASES IN SAN JOAQUIN COUNTY, CALIFORNIA. In U. S. Dept. 
Agr. Bur. Plant Indus. Circ. 23, 14 p. 
(12) Shapovalov, M., and Edson, H. A. 
1919. WOUND-CORK FORMATION IN THE POTATO IN RELATION TO SEED-PIECE 
decay. In Phytopathology, v. 9, no. 11, p. 483-496, 3 fig. Literature 
cited, p. 495-496. 
